Bath tub



FIG. 1 is a perspective view of a bath tub, according to my new design;

FIG. 2 is a front plan view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof.

The ornamental design for bath tub, as shown.